Circular strike



Dec. 1, 1964 E. L. SCHLAGE CIRCULAR STRIKE Filed Sept. 26, 1963 3 Sheets-Sheet 1 INVENTOR.

ERNEST L. SCHLAGE A TTORNE) Dec. 1, 1964 E. L. SCHLAGE 3,159,416

CIRCULAR STRIKE Filed Sept. 26, 1963 5 Sheets-Sheet 2 INVENTOR. ERNEST L. SCHLAGE AT TOPNEY E. L. SCHLAGE CIRCULAR STRIKE Dec. 1, 1964 Filed Sept. 26 1965 3 Sheets-Sheet I5 INVENTOR. ERNEST L. SCHLAGE A TTO/PNEY United States. Patent 3,159,4l6 CKRQULAR EFTRKKE Ernest L. Schlage, Burlhigarne, Calif., assignor to Schlage Lock Company, a corporation Filed Sept. 26, 1963, Ser. No. 311,315 17 tilaims. (Cl. 292-340) This invention relates to strike plates for door locks and more particularly to a strike having a substantially circular form.

The main object of the present invention is the provision of a strike which lends itself to installation into a bored circular opening formed on the door jamb so as to obviate much of the expense and time required in chiseling rectangular mortises and openings which heretofore have been necessary in the installation of the conventional strikes.

Another object of the invention is the provision of a strike that is substantially circular in shape and which is provided with means for rigidly securing it in a bored Opening in the jamb, said means providing optimum resistance to its being pulled or torn out of the door jamb.

Another object of the invention is'the provision of an improved circular strike of the type installed flush with the surface of the jamb.

Still another object of the invention is the provision of a strike and a method ofinstalling the same which method lends itself to the use of power driving boring equipment suitable for prcfabrication of door frames on which the strikes may be installed prior to shipping to a building site.

Yet another object of the invention is the provision of a strike having a latch bolt receiving opening which provides a maximum clearance in a vertical direction for the associated latch bolt thereby permitting larger installation tolerances and also allowing for vertical misalignment of the door and for door sag. 7

Yet another object of the invention is the provision of a circular strike which lends itself to rotation about the axis of the strike to permit the adjustment required to prevent door rattle in the event shrinkage results after the door has been installed.

Yet another object of the invention is the provision of a circular strike in which a strike box may be formed integrally therewith if desired.

Other objects and advantages will be apparent from the following specification and drawings wherein:'

FIG. 1 is an exploded perspective showing one form of the invention in association with the recess formed in the jamb and adapted to receive the strike therein. The iamb is shown horizontally disposed as it may be during the door frame building operation.

FIG. 2 is a side elevation of a portion of a door jamb showing the recess adapted to receive the strike therein with the frame, casing molding and doorstep omitted.

FIG. 3 is a side elevation of a jamb including casing molding and doorstop showing thestrike installed.

FIG. dis a horizontal cross section of the structure of FIG. 3 taken in a planeindicated by lines d4.

FIG; 5 is a front elevation of a modified strike adapted to receive two securing screws. 7

FIG. 6 is a side elevation of the strike of FIG. 5.

FIG. 7 is a side elevation of a boringtool adapted to form a recess that receives the flange formed on the strike.

FIG. 8 is a sideelevation of the tool of FIG. 7.

PEG. 9 is a perspective of a modified form of strike provided with an inclined lip for engaging the latch bolt.

FIG. 10 is a perspective of a strike formed without a strike box.

FIG. 11 is a perspective of another modified form of strike.

3,159,416 Patented Dec. 1, 1964 "ice FIG. 12 is a view similar to FIG. 4 but showing a modification of the recess that receives the strike.

FIG. 13 is a perspective of still another modified form of strike.

FIG. 14 is a cross section of the strike of FIG. 13 showing the same installed on a jamb.

H6. 15 is a perspective of another modified form of strike.

In detail, and first with reference to FIGS. 3 and 4, the invention is adapted to be employed on the vertically extending jamb l which is generally secured to a rough framing member 2 adjoining a wall panel 3. Usually a length of casing molding 4 is secured by nails passing through the wall panel 3 to the frame 2.

In FIG. 4 the associated door 6 is indicated in dot-dash lines and the outer face of such door is generally coplanar with the outer edge 7 (FIG. 1) of the jamb. The inner face of door 6 is adapted to abut astop 8 secured to the jarnb 1.

It will be noted that the width of the jamb between the outer edge '7 and the stop 8 is available for installation of the strike and as will subsequently be understood the present invention makes optimum use of the relatively narrow space available, and which space is roughly equal to the width of the door.

' One form of the strike of the present invention comprises a circular plate having a main planar portion 10 provided with an integral peripherally extending flange 11 which not only stitfens the plate but provides a means for enchancing the securernent of the strike to the jarnb in a manner that will subsequently be described. Integrally formed with the strike plate is a strike box having a relatively long, flat side 13 which extends dia-.

metrally of the plate and an opposite slantingly disposed side 14 which is connected to flat side 13 by curved junctures 15, 16 (FIG. 3). Said junctures and opposed sides are integrally connected to the bottom 18 of the strike box.

Centrally of the slanting side 14 there is provided a countersunk hole 19 for receiving therethrough a wood screw 25? for securing the strike to the jarnb 1. 1

To obtain optimum resistance to the strike being pulled out of the jamb 1 the latter is formed in the manner shown in FIG. 1. A relatively deep clearance hole 23 is bored about an axis 24 (FIG. 2) for receiving the strike box therein. Radially outwardly of the central clearance hole 23 there is provided a circular groove 24 which is of a width to receive the flange ll of the strike. Between the clearance hole 23 and the annular groove 24 an annular ridge 2d is provided the outer surface of which is spaced inwardly from the outer face of the jarnb 1 a distance about equal to the thickness or" the material forming the strike plate so that when the strike is installed the outer face of the planar portion N is coplanar with the outer face of the jamb 1.

Since the axis about which the hole 23 and groove 24 are formed is closer to the edge- 7 than the radius of the clearance hole 23, it will be noted that both the hole 23 and the groove 24 break out of the edge 7 as best seen in FIG. 1. Referring to FIG. 4 it will be seen that when the strike is installed the molding 4- may be placed against the free edge of the overhanging flange 11 so as to close up the opening in the edge 7 caused by boring the above mentioned hole and groove.

The above operation is conveniently performed by means of a boring tool shown in FIGS. 7 and 8. To the arbor St? of said tool there is secured by means of screws 31 a relatively flat blade 32; which is shaped and formed with cutting edges to provide a pair of cutting teeth 33 for forming the annular groove 24 and a lower cutting edge 35 for forming the clearance hole-23. Between the cutting teeth 33 and the central portion of the blade 32 cutting edges 34 are provided for forming the outer face J of ridge 25. The central point 36 is, of course, registered with the central axis 24 (FIGS. 1, 2) which represents the center of the clearance hole 23 and the groove 24.

It will be apparent that the coaction between the flange 11 of the strike and the groove 24 formed on the jamb creates a considerable resistance to the strike being pulled away from the jamb 1 upon rebound forces being applied to said strike by a slamming door. In this connection it will be seen with reference to FIG. 4 that the angle of the wood screw 20 is such that the strike is pulled inwardly of the outer face of the jamb 1 at assembly so that an effective gripping action is created between the free edge of the flange 11 and the wood of jamb 1. It should be noted that the bottom 18 of the strike box does not engage the bottom 37 of the clearance hole 23. By providing a slight clearance between the bottom of the strike box and the bottom 37 of the clearance hole 23 there is no tendency for the strike to tilt during the tightening process. In other words, engagement between the strike and the jamb takes place around the periphery at flange 11 thereby enhancing the connection between the strike and the jamb. After the strike has been installed, as described above, the molding piece 4 may be applied so as to abut the free edge of the flange 11 that projects outwardly from the edge 7 of the jamb. This creates a very neat assembly since the opening on the edge 7 of the jamb 1 is completely covered up.

An acceptable installation may be provided making the cutting edges 34 colinear with the cutting teeth 33 (FIG. 7) in which case the annular projecting ridge 25 is not formed and the jamb is cut as seen in FIG. 12. Despite the fact that the resistance of the projection 25 is thereby lost there still remains a substantial amount of wood that would have to fail in order to permit the strike to be pulled away from the jamb. In this connection it will be noted that the major diameter of the strike is greater than the width of the opening atthe edge 7 of the jamb so that the cuspashaped portions of the jamb adjacent edge 7 would have to fail in shear if the strike is to be pulled out forcibly. In the event it is desired to further increase the strength of the connection between the strike and the jamb, two screw holes may be provided as indicated by holes 40, 41 in FIGS. 5, 6 wherein a modified form of strike plate 42 is shown.

In FIG. 9 another modified form of strike indicated at 45 is shown wherein the juncture between the skirt 46 and the body portion 47 of the strike plate is modified at a point remote from the slanting face 48 of the strike box so as to provide a flat slanting surface 49 constituting a camming lip for engaging the slanting face of the latch bolt. This structure may be desirable in some instances where the latch bolt has a high heel and might tend to engage the strike at the axially extending sidewall of the latch bolt rather than at its slanting face.

Many of the advantagesof the present invention may be obtained even when the strike box is omitted as in the modified form of the invention shown at 52 in FIG. 10. In this case a lug 51 may be provided with a countersunk aperture 54- for receiving therethrough the securing screw. When such a structure is employed it is preferable to provide an inwardly directed flange 55 around the periphery of the latch bolt hole which functions to stiffen the strike in the absence of the strike box.

FIG. 11 shows a modified form of strike 56 which is similar to that shown in FIG. 1 except that an elongated slot 57 is provided for receiving screw 58. Such an elongated slot provides adjustment of the strike plate about its own axis so as to take up for any play which develops between the latch bolt and the corresponding face of the strike box. Furthermore, the provision of a slot 57 permits the assembly to be made with less care than might be required if a screw hole is provided since gripping action on the strike is effectively obtained at various position of the strike.

The present invention also contemplates a modified form in which the procedure for preparing the jamb is simplified in that it is necessary to bore only one hole. Such a modification is illustrated in FIGS. 13, 14 wherein the strike 60 is provided with a relatively wide circumferentially extending sidewall or skirt 61 the width of which is slightly greater than the depth of strike box 62, and consequently extends beyond the bottom of the strike box. As best seen in FIG. 14 the skirt 61 bottoms in hole 63 which is, of course, a plain cylindrical bore formed by a conventional boring bit.

In this form of the invention it is necessary to form the skirt with a notched portion 65 to clear the molding casing 66. It is also necessary to provide a clearance opening 67 (FIG. 14) in the skirt 61 to permit passage of the screw 68 therethrough.

It will be apparent that the structure of FIGS. l3, 14 is extremely rugged in construction and provides good securement to the jamb. Not only does the tightening of screw 68 urge the inner edge of the skirt 61 tightly against the bottom of bored hole 63, but the cusp-shaped portions of the jamb adjacent the edge 7 of the jamb have a greater effective area resisting those forces tending to pull the strike out of the jamb.

The general construction of FIGS. 13, 14 may be followed in making a strike that does not include an integral strike box. Such a modification is shown in FIG. 15. An alternative form of skirt applicable to both modifications of FIGS 13 and 15 is shown in FIG. 15 wherein the sidewall or skirt 70 is provided with a notch 71 for receiving therethrough the securing screw 72. The provision of a hole 67 (FIG. 14) is preferable to a notch (FIG. 15) since it is desirable to engage as much as possible of the length of the free edge of the skirt with the bottom of the bored hole. However from a manufacturing standpoint certain advantages accrue from the use of a notch 71 (FIG. 15).

The above specifically described preferred forms of the invention should not be taken as restrictive since it will be apaprent that various modifications in design may be resorted to without departing from the following claims.

I claim:

1. A strike for a door comprising:

a circular strike plate provided with a peripherally extending flange at right angles thereto,

a strike box formed integrally with said plate and having an open side for receiving a latch bolt therethrough,

said box being provided with one side adapted to be engaged by the corresponding face of a latch bolt positioned alongside said one side when such door is closed,

the side of said box opposite said one side being apertured to receive a securing screw therethrough.

2. A strike according to claim 1' wherein the portion of the annular juncture between said plate and said flange that is remote from said opposite side is formed with a slanting surface for engagement by the associated latch bolt when the door is closing.

3. A strike according to claim 1 wherein said one side extends diametrally of said plate to provide maximum clearance for such latch bolt.

4. A strike assembly for a door jamb comprising:

a circular strike plate including a strike box integral therewith received by said jamb,

said {3113b being provided with a pair of coaxial bored ho es,

the larger of said holes being relatively shallow and adapted to receive said plate therein and the smaller of said holes being relatively deep to receive said box therein,

said plate being provided with a peripherally ex tending flange substantially equal in width to the depth of said larger hole and adapted to be received in said larger hole.

5. In combination with a door jarnb a circular strike plate including a strike box integral therewith received on said jamb,

said plate being provided with a peripherally extending flange substantially at right angles to the plane of said plate,

said jamb being formed with an annular groove for receiving said flange therein and being formed with a central clearance hole concentric with said groove and inwardly thereof for receiving said box therein.

6. A strike assembly for a door comprising:

a door jamb,

a circular strike plate including a strike box integral therewith received on said jarnb,

said plate being provided with a peripherally extending flange substantially at right angles to the plane of said plate,

said jamb being formed with a counterbore for receiving said flange therein and being formed with a central clearance hole concentric with said counte bore and inwardly thereof for receiving said box therein.

7. A strike assembly comprising:

a strike including an integral strike box,

a door jarnb having a straight edge adjacent the outer face of an associated door in closed position,

a door stop on said jamb and spaced from said edge a distance substantially equal to the width of said door,

the face of said jamb between said edge and said stop being provided with a bored hole having a radius greater than the spacing between said edge and the center of said hole whereby said hole breaks out through said edge of'said jamb,

said hole being of sufiicient depth to receive said strike and box therein with the outer face of said strike substantially coplanar with said face of said jamb,

said strike being provided with a peripherally extending sidewall bottoming in said hole.

8. An assembly according to claim 7 wherein fastening means is provided for securing said strike plate and strike box to said jarnb.

9. An assembly according to claim 8 wherein said strike box is provided with an opening for receiving said fastening means therethrough.

10. A strike assembly comprising:

a door jamb having a straight edge adjacent the outer face of an associated door in closed position,

a door stop on said jamb and spaced from said edge a distance substantially equal to the width of the associated door for engaging the inner face thereof,

the face of said jamb between said edge and said stop being provided with a relatively large diameter shallow hole,

a relatively deep clearance hole in said 'jamb concentric with and of a smaller diameter than said shallow hole,

an apertured strike plate received in said holes,

the aperture in said strike plate being in registration with said clearance hole for receiving a latch bolt therethrough,

the radius of said clearance hole being greater than the spacing between said edge and the center of said holes whereby said holes break out through said edge of said jarnb,

said plate being provided with a peripheral flange on the side thereof that engages said jamb, and said flange being received in said shallow hole.

11. A strike comprising a substantially circular planar plate provided with a strike opening for receiving a latch bolt, an integral reinforcing flange on said plate and extending from the periphery thereof at a right angle to the plane of said plate, and means extending from said plate at the margin of said opening and at the same side as said flange for receiving a fastener for holding said flange against the jamb door.

12. A strike for use on a door jamb having a front face and an adjacent side edge at right angles to said front face and having a recess in said front face and'opening through said side edge, said recess being defined by a bottom and by a partially circular cylindrical side wall, said strike comprising a planar plate having a vertically elongated aperture therein overlying at least part of said recess, an arcuate flange integral with said plate and disposed adjacent to and conforming in contour with said sidewall, and means formed on said strike for receiving a fastener slantingly disposed relative to said plate for urging said flange away from said edge and against said bottom.

13. A strike as in claim 12 in which said receiving means includes an arcuate wall bounding one side of said aperture, the center of curvature of said arcuate wall being substantially the same as that of said side wall.

14. For use as a strike, an article of manufacture comprising:

a planar plate having a peripheral edge portion arcuately curved about a center in said plate and having an aperture generally defined by a straight edge passing substantially through said center and by a'curved edge concentric with said center,

a flange integral with said plate and extending from said peripheral edge portion and concentric with said center and terminating in a plane parallel to said plate,

an integral strike box defined by side walls extending from the edges of said aperture on the same side as said flange and by a bottom wall joining said side walls,

the side wall of said box extending from said curved edge of said aperture being provided with an opening to receive a fastening element therethrough.

15. A strike assembly comprising:

a door jarnb having a straight edge adjacent the outer face of an associated door in closed position,

a door stop on said jamb and spaced from said edge a distance substantially equal to the width of the associated door for engaging the inner face thereof,

the face of said jarnb between said edge and said stop being provided with a relatively large diameter shallow hole, and a relatively deep clearance hole concentric with and of a smaller diameter than said shallow hole,

an apertured strike plate having its peripheral margin received in said shallow hole,

the aperture in said strike plate being in registration with said clearance hole,

the radius of said clearance hole being greater than the spacing between said edge and the center of said holes whereby said holes break out through said edge of said jamb,

said strike plate being provided with a peripheral flange on the side thereof that engages said jamb with said flange being received in and conforming to the sidewall of said shallow hole.

16. A door strike comprising:

a generally circular plate formed to provide an integral strike box adapted to receive a latch bolt therein,

said box having a side adapted to be engaged by a face of a latch bolt when the associated door is closed,

said plate including a camming lip along one edge thereof and adapted to depress the latch bolt upon movement of the associated door to closed position,

said plate being provided with an integral flange extending outwardly from said plate on the same side thereof as said box and adapted to be received in a recess formed in the jarnb of such door,

said flange including arcuate portions at the periphery of said plate and extending along the parts of said periphery that are intermediate said side and said lip,

whereby said portions engage the side walls of said recess and resist outward movement of said plate in response to rebound forces impressed on said plate by said latch bolt.

17. A strike assembly adapted to cooperate with the latch bolt of an associated door comprising:

a door jamb having a vertically extending straight edge adjacent the outer face of such door in closed position,

a door stop on said jamb and spaced from said edge a distance substantially equal to the width of such door,

the face of said jamb between said edge and said stop being provided with a hole of sufficient depth to receive such latch bolt therein and having a radius greater than the spacing between said edge and the center of said hole whereby said hole breaks out through said edge of said jamb,

a substantially planar strike plate secured to said jamb,

said strike plate being formed with an arcuate peripheral portion having a center of curvature coincident with the center of said hole when said plate is so secured to said jamb,

said plate being provided with an aperture in registration with said hole for receiving such latch bolt therethrough,

the periphery of said aperture including a straight side extending parallel to said edge of said jamb and substantially through said center of curvature to permit optimum vertical clearance between said hole and the associated latch bolt, and

means integral with said plate at said aperture extending into said hole for receiving a fastener for securing said plate to said jamb.

References Cited by the Examiner UNITED STATES PATENTS ALBERT H. KAMPE, Primary Examiner. 

6. A STRIKE ASSEMBLY FOR A DOOR COMPRISING: A DOOR JAMB, A CIRCULAR STRIKE PLATE INCLUDING A STRIKE BOX INTEGRAL THEREWITH RECEIVED ON SAID JAMB, SAID PLATE BEING PROVIDED WITH A PERIPHERALLY EXTENDING FLANGE SUBSTANTIALLY AT RIGHT ANGLES TO THE PLANE OF SAID PLATE, SAID JAMB BEING FORMED WITH A COUNTERBORE FOR RECEIVING SAID FLANGE THEREIN AND BEING FORMED WITH A CENTRAL CLEARANCE HOLE CONCENTRIC WITH SAID COUNTERBORE AND INWARDLY THEREOF FOR RECEIVING SAID BOX THEREIN. 